Isotopes
Atoms of the same element with different numbers or neutrons but same number of protons.
Relative isotopic mass
The mass of an atom of an isotope compared with 1/12th of the mass of an atom of carbon-12.
Relative atomic mass
The weighted mean mass of an atom of an element compared with 1/12th of the mass of an atom of carbon-12.
Ionic bonding
The electrostatic attraction between positive and negative ions.
Covalent bond
The electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.
Atomic orbital
The region of space around the nucleus that can hold up to 2 electrons, with opposite spins.
Electronegativity
The ability of a bonded atom to attract the pair of electrons in a covalent bond.
First ionisation energy
The energy required to remove 1 mol of electrons from 1 mol of gaseous atoms of an element to form 1 mol of gaseous 1+ ions.
Metallic bonding
Electrostatic attraction between cations and delocalised electrons.
Disproportionation reaction
A reaction where the same element is both oxidised and reduced.
Enthalpy change of reaction
